Engrave for wood,bamboo,normal PCB,PVC,PMMA,plastic,duotone board(ABS)and etc nonmetal, also can engrave on gold,silver,copper, aluminium,Pb etc soft metal surface working.(Please pay more attention, this is wood working spindle, only can used for wood working and aluminum working,please dont use it for steel. If you need steel working,please check the metal spindle,thank you!